The present disclosure generally relates to a system for measuring the uniformity of heat distribution within the heating chamber of a furnace during a heat treatment process, such as, for example, annealing, normalizing, hardening, tempering, and case hardening of ferrous alloys, brazing of metallic components, and the sintering of powder metal shapes in air, vacuum, and reducing atmospheres, typical heat treating atmospheres, having temperatures ranging from about 500° C. to about 1,300° C. More specifically, the disclosure concerns a device that measures the relative maximum temperature witnessed as determined by the shrinkage of the device per a prepared calibration table without contaminating the furnace atmosphere.
Current practice for the metal heat-treating industry to determine the uniformity of heat distribution during a heat treatment process is to utilize thermocouples placed at specific sites throughout the heating chamber to conduct a temperature uniformity survey. These thermocouples, then, have to be connected to a sensing/recording device to measure the temperature at each specific site. The sensing/recording device can be external or internal to the heating chamber, but in either case the process is cumbersome and can actually distort the heat-treating process due to the added weight of the internal sensor/recorder. The measurement of the heat distribution uniformity is a requirement to insure that all the parts being treated received the correct level of heat to assure the heat treatment process was effective.